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    <title>Document</title>
    <script>
        //字符串+数字 结果就等于字符串 张三20
        console.log("张三"+20+"岁");

         var age = 20;
        console.log('张三 age');
        console.log('张三'+age); //输出到控制台的都是变量在内存中保存的值

        var str1 = 'aa"bb"cc';//可以用''包含""
        var str2 = "aa'bb'cc";//可以用""包含''

        console.log(str1);
        console.log(str2);

         var str3 = 'abb'+'ab'+'ab"abc"cc'+'cc'
        var str4 = "ab'abc'ac"

        console.log(str3);
    </script>
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